These are templates that are used to construct all the titles and descriptions for those items. As such, they are built using placeholders with %% signs on both sides. The exact meaning of each placeholder is explained in Yoast’s documentation, but defaults should get you started.
The placeholders are replaced by Yoast with the actual post/category titles or even the category or tag description as entered in WordPress.

Post specific settings

Besides the global templates you can customize the title or meta description for a particular listing, using the “WordPress SEO by Yoast” metabox that appears when editing the listing in the admin:

Only the “SEO Title” and “Meta Description” fields are supported. They override the global templates if specified.

Category or tag specific settings

Similar to post-specific settings you can customize the title or meta description to be used in the page of a particular category or tag, using the section added by Yoast to the page where a category or tag is edited. This section can be found via Directory – Directory Categories or Directory – Directory Tags:

Only the “SEO Title” and “SEO Description” fields are supported and will override the global templates if specified, when browsing that specific category or tag.

How to…

… customize the main page information?

Since the main page (the one with the [ businessdirectory ] shortcode) is a regular page, Yoast treats it as such. In this case you must use the title templates for “Pages” or just use the metabox that appears when trying to edit the page.

Refer to “Post, category and tag global settings” if you want to change the template used to construct the title and meta description tag for all listings, or to “Post specific settings” if you want to change how a particular listing gets its title/meta description tags.

Don’t use Force Rewrite–this is BAD
The option “Force Rewrite Titles” causes all sorts of havoc with your site, titles, and output from Yoast. Even Joost himself doesn’t recommend using this setting unless you truly understand what you’re doing. Our experience is that is completely breaks the output for Yoast with BD, so DO NOT USE THIS SETTING.